NOTE: Sealed Lead Acid batteries come charged from the factory. Their shelf life is approximately 9 months before use and required recharging. You must make sure that these batteries are always charged; therefore if they sit on your shelf we suggest that you charge them every 2 months. Store at a cool temperature. Higher temps will lead to increased discharge on the shelf. Lead Acid batteries may not recharge if sitting on the shelf too long without a recharge. When installed in their respective pieces of equipment they will then receive a trickle charge.